This work investigated the microstructure and tensile deformation behavior of Ti-6Al-4V alloy fabricated using a high-power laser solid forming (LSF) additive manufacturing. The results show that the ...post-fabricated heat-treated microstructure consists of coarse columnar prior-β grains (630–1000 μm wide) and α-laths (5–9 μm) under different scanning velocities (900 and 1500 mm/min), which caused large elongation (∼18%) superior to the conventional laser additive manufacturing Ti-6Al-4V alloy. The deformation behavior of the LSF Ti-6Al-4V alloy was investigated using in situ tensile test scanning electron microscopy. The results show that shear-bands appeared along the α/β interface and slip-bands occurred within the α-laths, which lead to cracks decaying in a zigzag-pattern in the LSF Ti-6Al-4V alloy with basket-weave microstructure. These results demonstrate that the small columnar prior-β grains and fine basket-weave microstructure exhibiting more α/β interfaces and α-laths can disperse the load and resist the deformation in the LSF Ti-6Al-4V components. In addition, a modified microstructure selection map of the LSF Ti-6Al-4V alloy was established, which can reasonably predict the microstructure evolution and relative grain size in the LSF process.
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The nature of the phases, phase transitions, and their magnetic characteristics all play an essential role in the performance of Ni-Mn-In Heusler alloys, both as magnetic shape memory and giant ...magnetocaloric effect (MCE) materials. The details of the structural and magnetic transformations in Ni44.9Mn43In12.1 Heusler alloy are reported in this work, using synchrotron and neutron diffraction and AC-SQUID susceptibility results. Of special interest is the affirmation of an antiferromagnetic (AFM) phase and the exclusion of a spin-glass state as the cause of the observed drop in magnetization upon cooling. This is of critical importance for magnetocaloric applications because of the dominant contribution to MCE of the magnetic entropy change upon phase transformation.
A new nonlinear planar beam formulation with stretch and shear deformations is developed in this work to study equilibria of a beam under arbitrary end forces and moments. The slope angle and stretch ...strain of the centroid line, and shear strain of cross-sections, are chosen as dependent variables in this formulation, and end forces and moments can be either prescribed or resultant forces and moments due to constraints. Static equations of equilibria are derived from the principle of virtual work, which consist of one second-order ordinary differential equation and two algebraic equations. These equations are discretized using the finite difference method, and equilibria of the beam can be accurately calculated. For practical, geometrically nonlinear beam problems, stretch and shear strains are usually small, and a good approximate solution of the equations can be derived from the solution of the corresponding Euler–Bernoulli beam problem. The bending deformation of the beam is the only important one in a slender beam, and stretch and shear strains can be derived from it, which give a theoretical validation of the accuracy and applicability of the nonlinear Euler–Bernoulli beam formulation. Relations between end forces and moments and relative displacements of two ends of the beam can be easily calculated. This formulation is powerful in the study of buckling of beams with various boundary conditions under compression, and can be used to calculate post-buckling equilibria of beams. Higher-order buckling modes of a long slender beam that have complex configurations are also studied using this formulation.
•A new nonlinear planar beam formulation with stretch and shear is developed.•The formulation can deal with large deformation and avoid shear locking.•A simple approximate solution is derived for an Euler–Bernoulli beam.•Buckling of beams under compression are studied.•Post-buckling equilibria of beams are also calculated.
P2X receptors are ATP-gated cation channels composed of one or more of seven different subunits. P2X receptors participate
in intestinal neurotransmission but the subunit composition of enteric P2X ...receptors is unknown. In this study, we used tissues
from P2X 3 wild-type (P2X 3 +/+ ) mice and mice in which the P2X 3 subunit gene had been deleted (P2X 3 â/â ) to investigate the role of this subunit in neurotransmission in the intestine. RT-PCR analysis of mRNA from intestinal tissues
verified P2X 3 gene deletion. Intracellular electrophysiological methods were used to record synaptic and drug-induced responses from myenteric
neurons in vitro . Drug-induced longitudinal muscle contractions were studied in vitro . Intraluminal pressure-induced reflex contractions (peristalsis) of ileal segments were studied in vitro using a modified Trendelenburg preparation. Gastrointestinal transit was measured as the progression in 30 min of a liquid
radioactive marker administered by gavage to fasted mice. Fast excitatory postsynaptic potentials recorded from S neurons
(motoneurons and interneurons) were similar in tissues from P2X 3 +/+ and P2X 3 â/â mice. S neurons from P2X 3 +/+ and P2X 3 â/â mice were depolarized by application of ATP but not α,β-methylene ATP, an agonist of P2X 3 subunit-containing receptors. ATP and α,β-methylene ATP induced depolarization of AH (sensory) neurons from P2X 3 +/+ mice. ATP, but not α,β-methylene ATP, caused depolarization of AH neurons from P2X 3 â/â mice. Peristalsis was inhibited in ileal segments from P2X 3 â/â mice but longitudinal muscle contractions caused by nicotine and bethanechol were similar in segments from P2X 3 +/+ and P2X 3 â/â mice. Gastrointestinal transit was similar in P2X 3 +/+ and P2X 3 â/â mice. It is concluded that P2X 3 subunit-containing receptors participate in neural pathways underlying peristalsis in the mouse intestine in vitro . P2X 3 subunits are localized to AH (sensory) but not S neurons. P2X 3 receptors may contribute to detection of distention or intraluminal pressure increases and initiation of reflex contractions.
To investigate the signaling pathways after astrocytes were activated in neuropathic pain.
Thirty-six Sprague Dawley (s.d.) rats were randomly divided into two groups (each group with 18 s.d. rats) ...including chronic constriction injury (CCI) of the sciatic nerve model group and sham operation group. Operation was perform ed on the right leg in all rats. The lumbar spin al cord (L4 and L5) was taken to make paraffin slices on the 1st day before operation and the 1st, 3rd, 7th, 14th and 28th day after operation in each group. Paraffin slices were labeled with p38 mitogen-activated protein kinase (p38MAPK) and c-Jun N-terminal kinase (JNK) by immunofluorescence staining, and then were co-labeled with hexaribonucleotide binding protein-3 (NeuN), glial fibrillary acidic protein (GFAP) and anti-integrin αM (CD11b) antibody (OX-42) to explore the associations of p38MAPK and JNK with nerve cells or glial cell.
Compared with sham group, the pain threshold was significantly decreased, and astrocyte-activated markers, GFAP and vimentin were significantly increased in CCI group. The mean fluorescence intensities of p38MAPK and JNK were increased in the right spinal dorsal horn of CCI group. The coexpression of JNK and GFAP was found in astrocytes of the spinal dorsal horn in CCI group.
JNK signal transduction pathway is involved in the pain signaling transduction of astrocytes.
Elderly patients may have limited ability to read and comprehend medical information pertinent to their health.
To determine the prevalence of low functional health literacy among community-dwelling ...Medicare enrollees in a national managed care organization.
Cross-sectional survey.
Four Prudential HealthCare plans (Cleveland, Ohio; Houston, Tex; south Florida; Tampa, Fla).
A total of 3260 new Medicare enrollees aged 65 years or older were interviewed in person between June and December 1997 (853 in Cleveland, 498 in Houston, 975 in south Florida, 934 in Tampa); 2956 spoke English and 304 spoke Spanish as their native language. MAIN OUTCOME MEASURE; Functional health literacy as measured by the Short Test of Functional Health Literacy in Adults.
Overall, 33.9% of English-speaking and 53.9% of Spanish-speaking respondents had inadequate or marginal health literacy. The prevalence of inadequate or marginal functional health literacy among English speakers ranged from 26.8% to 44.0%. In multivariate analysis, study location, race/language, age, years of school completed, occupation, and cognitive impairment were significantly associated with inadequate or marginal literacy. Reading ability declined dramatically with age, even after adjusting for years of school completed and cognitive impairment. The adjusted odds ratio for having inadequate or marginal health literacy was 8.62 (95% confidence interval, 5.55-13.38) for enrollees aged 85 years or older compared with individuals aged 65 to 69 years.
Elderly managed care enrollees may not have the literacy skills necessary to function adequately in the health care environment. Low health literacy may impair elderly patients' understanding of health messages and limit their ability to care for their medical problems.
In this work we showcase the emitter
in which we employed a twin-emitter design of our previously reported material,
. This new system presented a red-shifted emission at 488 nm compared to that of
...at 475 nm and showed a comparable photoluminescence quantum yield of 57.1% in a 20 wt % CzSi film versus 63.3% for
. The emitter was then incorporated within a solution-processed organic light-emitting diode that showed a maximum external quantum efficiency of 8.4%, with Commission Internationale de l'Éclairage coordinate of (0.22, 0.47), at 1 mA cm
.
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